1. Field of the Invention
The invention relates to an output method and apparatus for generating a pattern in accordance with data supplied from an external device such as a host computer or the like.
2. Related Background Art
FIG. 2 is a block diagram showing a flow of processes in a conventional printer 1.
In FIG. 2, reference numeral 2 denotes an external device such as a host computer or the like which generates print data; 3 an input unit which receives data; 4 an analyzer to analyze the input data; 5 a page buffer to store the result of the analysis; 6 a developer to develop data into an output image of a bit map memory or the like on the basis of the content in the page buffer 5; and 7 a frame memory to store the developed output image. The frame memory 7 comprises an RAM. Reference numeral 8 denotes an output unit to control an output mechanism 9 by, for instance, a laser beam or the like in accordance with the image stored in frame memory 7. Reference numeral 10 denotes a recording medium such as a paper or the like.
In the printer 1, the print data generated from the external device 2 is received by the input unit 3 for receiving the data, the analyzer 4 analyzes the received data, and data of a format to give an instruction to the developer 6, namely, the page buffer 5 is formed as a result of the analysis. The page buffer 5 is formed on a page unit basis and is sent to the developer 6 in a form including all of the information of one page. In accordance with the page buffer 5, the developer 6 forms an output image into the frame memory 7 in a form of, for example, a binary bit map memory of one page. In accordance with the frame memory, the output unit 8 records the result of the printing to the recording medium such as a paper or the like by, for instance, controlling a laser beam of the output mechanism 9.
In the above conventional apparatus, however, the frame memory for storing the output image must be reserved for an amount of data corresponding to one whole page, so that it is impossible to control the device so as to efficiently use the memory in accordance with the size of the output image. For instance, when a page of the A4 size is generated at a resolution of, e.g., 300 dpi (dots per inch), even in the case where only one point of a size of one dot is generated, it is necessary to fixedly reserve a frame memory of about one Mbyte which is necessary to store the output image of the whole page. Further, in the case of performing a color expression or a dark/light expression, such a problem becomes further serious.